Radiation Protection Adviser

Issue 14 October 1998

CONTENTS

Welcome to the fourteenth edition of the Radiation Protection Adviser.
This issue includes a further update on progress with revising the
Ionising Radiations Regulations 1985 (IRR85).

We have reviewed your responses to the readership survey, included
with Issue 12, and decided that RPA News will continue in its existing
form, at least until the revised regulations are introduced. It will
also continue to be a free publication.

RPA News was originally aimed at RPAs only but since it was launched
the readership has widened considerably. To reflect this, we are considering
changing the title to Radiation Protection News - we would appreciate
your comments.

THE REVISED REGULATIONS:THE STORY CONTINUES

Issue 13 of the Radiation Protection Adviser gave details of
the formal Consultative Document (CD) published by the Health and Safety
Commission (HSC). In May, and thanks to the good offices of the Society
for Radiological Protection, the HSE team made a series of presentations,
starting in Glasgow, finishing in Cardiff, and taking in London, Chilton
and Manchester on the way. The seminars allowed HSE to set out some
of the key issues in the CD, but with plenty of time for comments from
the audience. Total attendance exceeded 300, which was very pleasing.
Equally pleasing was the level of understanding of the proposals, as
demonstrated by many of the questions and observations. Some of the
main themes to emerge from the seminars were:

Justification

There was little criticism of the proposed justification requirement
itself, but concerns were expressed, particularly from the medical sector,
about how it would operate in practice. We recognise that the operative
procedures for considering justification have yet to be developed.

Prior authorisation

It seems likely that the use of X-ray sets for medical treatment would
also need to be covered by the relevant regulation. However, the main
interest focused on the sub-regulatory activities; the development of
generic authorisations and procedures.

Risk assessment

The basic requirement for prior risk assessment seemed uncontroversial.
The issue which raised more discussion was its potential combination
with the risk evaluation for accidents (the updated version of IRR85
Regulation 25). Views on this seemed to be fairly evenly balanced.

Restriction of exposure

The main discussion issue here was the 'ALARP investigation' and whether
the 15 mSv dose level remained appropriate - again views on this varied.
The other substantive regulatory changes here, including treatment of
female employees, produced little comment.

Dose limitation

Discussion was focused, not so much on the direct choice between Options
A and B for the adult worker dose limit, but on the operation of the
procedures within the options. There was also considerable interest
in the proposed flexibility for the public dose limit relating to exposure
from patients administered with radiopharmaceuticals.

Radiation Protection Advisers (RPAs

)
There seemed to be little support for the status quo in IRR85 and little
opposition to the basic regulatory scheme set out in the CD. Most of
the comments centred on the workings of the recognition scheme itself
and we appreciate that, once the regulatory requirements are settled,
much work is needed on this aspect. We also were given a clear message
that the requirement for written appointment of RPAs should be retained!

Designated areas

There was a range of views on the level of flexibility introduced into
the draft revised regulations. However, the potential for confusion
over 'specified systems of work' and 'local rules' was illustrated at
one seminar in discussing how the draft regulation might affect dentists
and this will need further thought.

Notification of spillages

The approach in the CD was based on using multipliers of values of individual
nuclide quantities and concentrations that would appear in a schedule
to the regulations. A number of comments suggested that the total quantity
thresholds for this requirement would, for certain commonly used radionuclides,
lead to notification of spillages to HSE with much greater frequency
than is the case under IRR85, particularly in the medical sector. Clearly
further work is needed on this, since the purpose of statutory notification
is to draw to HSE's attention the more serious situations, giving HSE
the option to conduct its own investigation.

Written comments on CD

We stressed at the seminars that HSC could only formally take account
of written comments sent in on the CD. The message seems to have been
heeded, as nearly 200 substantive replies were received! We have been
analysing these and identifying where further change seems merited.
The next stage is to put the proposals for the final version of the
revised regulations and Approved Code of Practice to HSC's Ionising
Radiations Advisory Committee (IRAC), and, subject to IRAC's views,
on to HSC itself.

There was almost universal support from the comments received that
the main parts of the regulations should be operative from 1 January
2000. Though the timetable remains tight, we are still on course for
the revised regulations to be made and laid before Parliament in the
summer of 1999. If achieved, this would allow duty holders several months
to ensure they will be in compliance with the revised regulations by
the operative date.

Conclusion

The task of analysing the comments, though daunting, was nonetheless
rewarding for the ideas it provided to further improve the CD proposals.
We are pleased that the earlier message asking for supportive as well
as critical comments was heeded, as it helped to avoid introducing change
where there was demonstrable support for the CD proposals. We are extremely
grateful for the time and effort taken by all those who sent their comments
or who have contributed within their organisations to a corporate response.

HSE has identified problems with two test houses offering examination
and testing of radiation monitors for employers in the non-destructive
testing (NDT) sector. The tests were insufficient to assure the performance
of the monitors used during industrial radiography.

HSE carried out a limited campaign to increase the awareness of NDT
employers about their responsibilities and to give general advice on
testing. We thought that readers would be interested as the advice is
applicable to employers all sectors, not just NDT employers

Under regulation 24 IRR85, it is the employer's duty to ensure that
monitors are thoroughly examined and appropriately tested by a qualified
person - Issue 12 of the Radiation Protection Adviser also gave
advice.

The NDT employers were asked to consider in what circumstances monitors
needed to be used and, in consultation with their RPAs, what minimum
tests would be appropriate. The exact use of the monitors depends on
the location and the circumstances during the radiography, but it is
possible to identify common aspects, for example:

routine use of a monitor to ensure proper designation of any supervised
or controlled areas set up around work areas;

use of a monitor at the end of a radiation operation, to ensure
that the exposure had terminated, or during gamma radiography, used
to ensure that the source had retracted fully into the shielded container;

use of a monitor after foreseeable incidents as set out in contingency
plans drawn up under regulation 27 of IRR85.

We were pleased to see that RPAs consulted on this issue gave similar
advice. Therefore, HSE has suggested appropriate minimum tests for monitors
used in the general run of mainstream industrial radiography. A thorough
examination would generally include a test:

of the linearity of response and calibration over the whole range
of dose rates likely to be encountered (usually extending from 2.5
µSvh-1 to, at least, 2 mSvh-1 and often up to
5 mSvh-1); and

to ensure that the monitor responds appropriately to a dose rate
greater than the maximum which it can record.

Also, where the monitor is used in X-radiography at energies less than
150 kV, the tests would normally need to give assurance of the response
at lower energies. This can be done by testing the monitor's response,
over part of the dose rate range, to radiation emitted from an 241Am
check source. It should be possible to carry out the tests at the highest
dose rates without positioning the radiation monitor too close to the
radiation source. A distance shorter than 100 mm would usually be insufficient.

All employers need to be able to identify the minimum level of testing
required for their monitors. Normally, this would be done in consultation
with the appointed RPA and, frequently, the qualified person in the
test house. In any event, the employer needs to be satisfied that the
test house is able to complete the required tests in a competent manner.

IRR85 - NEW CERTIFICATE OF APPROVAL

HSE has recently issued a new certificate of approval under IRR85,
Schedule 2, giving values for barium-137. The certificate was granted
when HSE became aware that barium-137m was being used in relatively
small quantities in the education sector and there were no specific
values in schedule 2 IRR85; the default numbers for other nuclides were
thought to be unreasonably restrictive. The new values were calculated
on the same basis as the values for other radionuclides in schedule
2 IRR85. A copy of the certificate is available from the Editor.

PUBLICATIONS

CIDI Dose trends report

HSE published the second dose 'trends report' in July 1998, covering
the period 1990 to 1996. Free copies of the report , Occupational
exposure to ionising radiation 1990 - 1996 - analysis of doses reported
to the Heath and Safety Executive's Central Index of Dose Information,
are available from the Editor, see front page for address.

The major part of the the report is also available on HSE's web site
- http://www.open.gov.uk/hse/cidi2.pdf

For classified persons as a whole the data on CIDI suggest that, in
general, employers have continued with the successful reduction of exposures
reported in the first trends report. When the special case of non-coal
miners is excluded, the number of classified persons exceeding the investigation
level in IRR85 (15mSv) had fallen to 17 by 1996 compared with the 1986
figure of 1,911 (after corrections for notional doses).

Critical examination of x-ray equipment

The Institute of Physics and Engineering in Medicine has recently published
a report looking at the ccritical examination of x-ray generating
equipment in diagnostic radiology, Report 79, ISBN 0-904181-89-8,
priced £8. This gives advice on the requirement in regulation 32 IRR85
on persons installing or erecting articles for use in work with ionising
radiation.

Earlier this year HSE published revised guidance on respiratory protective
equipment, the selection, use and maintenance of respiratory protective
equipment, HS(G)53, ISBN 0-7176-1537-5, priced £9.50. Copies are
available from HSE Books, see front page for address. This practical
guide revises the 1990 version of HS(G)53 and replaces EH53, Respiratory
protective equipment for use against airborne radioactivity.